In the PDFs the page numbering starts after the index page but in Adobe reader cover page is assigned as page no. 1 so there is discrepancy in page numbers when I try to go to a specific page in the PDFs . I have ipad Air 2 please tell me the settings to reassign the pages
It is not possible to reassign or change page numbers in Acrobat Reader application either you are using it on desktop or on your mobile device.
You will need the desktop version of Acrobat application to make these changes.
Please note that Acrobat Reader mobile apps for iOS and Android display physical page numbers (starting from 1), not page labels (e.g. i, ii, iii, iv) or logical page numbers.
Thus, even if you change the page labels of your PDF document using Acrobat Pro/Standard (paid desktop app), the first page number displayed in Acrobat Reader mobile apps will still be 1.
Sorry for the inconvenience.